Try using separate workers for each TUN/TAP connection (sometimes produces duplicate packets when communicating with both the node address and a subnet address, sometimes also can't Ctrl-C to quit)

src/tuntap/conn.go

@@ -0,0 +1,75 @@
+package tuntap
+
+import (
+	"errors"
+
+	"github.com/yggdrasil-network/yggdrasil-go/src/yggdrasil"
+)
+
+type tunConn struct {
+	tun  *TunAdapter
+	conn *yggdrasil.Conn
+	send chan []byte
+	stop chan interface{}
+}
+
+func (s *tunConn) close() {
+	close(s.stop)
+}
+
+func (s *tunConn) reader() error {
+	select {
+	case _, ok := <-s.stop:
+		if !ok {
+			return errors.New("session was already closed")
+		}
+	default:
+	}
+	var n int
+	var err error
+	read := make(chan bool)
+	b := make([]byte, 65535)
+	for {
+		go func() {
+			if n, err = s.conn.Read(b); err != nil {
+				s.tun.log.Errorln(s.conn.String(), "TUN/TAP conn read error:", err)
+				return
+			}
+			read <- true
+		}()
+		select {
+		case <-read:
+			if n > 0 {
+				s.tun.send <- b[:n]
+			}
+		case <-s.stop:
+			s.tun.log.Debugln("Stopping conn reader for", s)
+			return nil
+		}
+	}
+}
+
+func (s *tunConn) writer() error {
+	select {
+	case _, ok := <-s.stop:
+		if !ok {
+			return errors.New("session was already closed")
+		}
+	default:
+	}
+	for {
+		select {
+		case <-s.stop:
+			s.tun.log.Debugln("Stopping conn writer for", s)
+			return nil
+		case b, ok := <-s.send:
+			if !ok {
+				return errors.New("send closed")
+			}
+			if _, err := s.conn.Write(b); err != nil {
+				s.tun.log.Errorln(s.conn.String(), "TUN/TAP conn write error:", err)
+				continue
+			}
+		}
+	}
+}